The present invention relates to a vehicle exterior component arranged in a front portion of the body of a vehicle.
It is known that at least a part of a vehicle exterior component arranged in a front portion of the body of a vehicle, such as a hood or a front fender, may be configured by a plastic honeycomb structure to reduce the weight of the vehicle. The honeycomb structure includes a honeycomb portion, an inner plate portion, and an outer plate portion. The honeycomb portion is configured by a plurality of tubular cells, which are separated from one another by partition walls. The inner plate portion is located on a side of the honeycomb portion that is closer to the engine compartment. The outer plate portion is arranged on a side of the honeycomb portion that is farther from the engine compartment. The outer plate portion and the inner plate portion hold the honeycomb portion from the outer side and the inner side, respectively, to seal the cells.
A sound absorbing configuration that absorbs sound waves generated in an engine compartment by means of a honeycomb structure is known (see, for example, Japanese Laid-Open Patent Publication No. 61-249853). The sound absorbing configuration has communication holes formed in an inner plate portion, which allow communication between the engine compartment and the interior spaces of cells. In this sound absorbing configuration, if sound waves are generated in the engine compartment and have frequency equal to the natural frequency of the air in each communication hole, the sound waves enter the cells through the communication holes and thus resonate. The resonating sound waves are then absorbed through friction with respect to the wall surfaces of the communication holes.
According to Japanese Laid-Open Patent Publication No. 61-249853, partition walls configuring cells have an opening that allows communication between at least two adjacent cells. The purpose of the opening is to enlarge the resonance frequency range.
The configuration of the aforementioned publication reduces sound in the engine compartment, thus decreasing noise emitted from the vehicle. However, the honeycomb structure of the vehicle exterior component is highly rigid, and the vehicle exterior component resists deformation when contacting an obstacle outside the vehicle. This lowers performance of this configuration for attenuation of impact applied to the obstacle.